Which device is used to limit system pressure by venting excess pressure?

• A. Relief valve
• B. Gate valve
• C. Poppet valve
• D. Ball valve

Answer: (A)

When system pressure gets too high, a relief valve opens to vent the excess pressure and protect the equipment. It is set to a specific pressure, and once that limit is reached, the valve shifts to allow fluid to escape, lowering the pressure. It then reseats once the pressure drops back to a safe level. This safety function distinguishes it from shut-off valves like gates or balls, which are used to start or stop flow and do not automatically vent. A poppet valve is a general valve element used in many configurations, but it isn’t inherently the device that limits pressure by venting.